1. Technical Field
The present invention relates to an electronic structure, and associated method of fabrication, for coupling a heat spreader above a chip to a chip carrier below the chip.
2. Related Art
A chip on a chip carrier may have a heat spreader on a top surface of the chip, such that the heat spreader is directly coupled to the chip carrier by an adhesive material that encapsulates the chip. If the heat spreader and the chip carrier have about a same coefficient of thermal expansion (CTE), then the adhesive material helps keep the chip carrier-chip-heat spreader structure approximately flat during thermal cycling. Nonetheless, cracking resulting from thermal cycling has been observed to occur at the surface of the chip carrier where a bounding surface of the adhesive material contacts the chip carrier. The cracking can propagate into the chip carrier and damage circuit lines within the chip carrier.
A method and structure is needed for preventing said damage to said circuit lines within the chip carrier.